I brewed a cream ale extract kit 3weeks ago and used Irish moss in the last 15 minutes of the boil. I had it fermenting via swamp cooler at 64. I still have a thick foam but no airlock activity. I was wondering if this is normal with the use of Irish moss or could it be signs of infection. Any guidance is much apprecitated. Thanks.
Foam but no bubbling in the airlock is a sign of a leaky lid. Not a problem.
You did not say when you brewed or how long it was fermenting. Quite often I have foam on top after bubbles are done. Swirl the vessel and the foam will likely drop out if fermentation is done.
Edit - you did say 3 weeks ago, so my comment stands. Give it a swirl and it should settle out.